It would be an understatement to say philosophy can be difficult, which is perhaps why there are all those books doing the rounds promising to make it easier for idiots such as myself. Gilles Deleuze is no exception. What is one to make of a passage like this? "To learn to swim is to conjugate the distinctive points of our bodies with the singular point of the objective Idea in order to form a problematic field." I have quoted this from Difference And Repetition and I must confess that, though I have read it numerous times, I have absolutely no idea what he is talking about. Nevertheless, like the Trojan I am, I soldiered on with the book and found it extremely rewarding in terms of many of its underlying ideas. In this essay, I hope to do justice to some of them. The 'dark precurser' to Difference And Repetition seems to be Kant, whose achievement Deleuze recognises as both formidable and problematic. Kant of course can be equally recondite and obscure - a 'vice' Schopenhauer said was due to his not understanding his own ideas himself. (Would one dare say that of Deleuze? I wonder.) Kant can also be lucid when he gets into his stride, as indeed can Deleuze. In this essay, I promise to be as lucid as possible, but won't promise to always keep my promise. We are, after all, dealing with difficult ideas. While reading Deleuze, I was struck by the resemblance between some of his ideas and those of the Sankhya school of Hindu philosophy related to the dual figures of Purusha and Prakrti - a subject I dealt with in a previous essay. According to Deleuze, Kant's thought is oriented towards what it takes to actively synthesise ideas from empirical raw materials. In other words, it is oriented towards conscious representation of ideas and impressions by actively organising them through the already known concepts of the understanding and creating a sort of hierarchy, which becomes more abstract the higher up the hierarchy you go. Deleuze describes what's involved here as active synthesis, whereby a subject grasps objects of thought or sensation and transforms them into something more complex through synthesising them. He contrasts this with passive synthesis, whereby a subject passively registers sensations or thoughts. This is characterised by contemplation rather than action. As far as I can see, the difference is like that between voluntary looking and involuntary seeing, the first of which is active, the second passive. This has something in common with the parts played by Purusha and Prakrti. In Sankhya thought. Purusha is passive, pure consciousness, consciousness as witness while Prakrti is identified with the active mind-body complex and the phenomenal world. It is interesting that Prakrti is depicted as female and Purusha as male, and the Prakrti seduces Purusha into a web of illusion. The difference between this Hindu concept and Delauze's idea of the passive and active synthesis is that Deleuze tends to pathologise the passive synthesis in a way that the Sankhya school of thought, which I suspect is not free of ascetic Hindu moralism, does not. It is narcissistic and lacks the realism implicit in the active synthesis. It is the passive synthesis that is at work in dreams and delusions and, of course, it plays a big part in the creation of art and poetry. In Freudian terms, one might perhaps associate it with the Pleasure Principle, while the active synthesis is more associated with the demands of the Reality Principle. So in a sense it is as if we were trying to escape the gravitational field of the earth through active synthesis, while passive synthesis kept thwarting our efforts and pulling us back down. Active synthesis aims for a more objective view of the 'real' (actual) world, while passive synthesis generates a 'virtual' world more in tune with our unconscious predilections. (As Deleuze says, the virtual is as real in its own terms as the actual, just as dreams are as real in their own terms as waking life is in its own terms, so no hierarchy of values based on the more real and the less real is being suggested here. In fact, the real is not opposed to the virtual, but to the possible.) Consciousness characterises active synthesis, while the unconscious characterises passive synthesis. This may not, of course, be how Deleuze would describe it, but that's the sense I get from his words. The problem with Kant's active synthesis, according to Deleuze, is that it is disembodied. He fully acknowledges the significance of Kant's Copernican Revolution in thought, but like most bourgeois revolutions, it tended to stop half-way. It replaced the absolute monarchy of reason with a constitutional one. It did not go far enough in decentring the human subject, because of the way it privileged the subject-object relation in thought. Of course, Kant recognised that what grounded the subject - the 'I', like the Eye in The Upanishads, which sees but cannot see itself seeing - was as unknowable in itself as the thing in-itself behind the object of any perception. Nevertheless, he attributed a kind of unity to it which belies its often fragmentary forms. So for Deleuze, the Copernican Revolution in philosophy had to be carried much further and a new 'transcendental ground' of this disembodied subject of cognition had to be developed. Just as the Copernican Revolution was only one stage in the evolution of astronomy, Kant's 'Copernican Revolution' in philosophy was only one stage in the history of philosophy. Deleuze would carry Kant's revolution further by providing it with a perspective influenced strongly by Darwin, Nietzsche, Freud and Melanie Klein. In other words, he wanted to shift the focus from the Apollonian to the Dionysian aspects of the Self. Dionysus, of course, was the god who was ritually dismembered by his worshippers; so he seems an appropriate symbol for the fractured subject, which is of such concern to Deleuze. What this means is that behind Kant's active synthesis of the intellect and cognition lies the passive synthesis of the unconscious which is rooted in the body, which itself, of course, is rooted in the physical constitution of the universe in such a way that the subject is far from being sovereign in its own realm. In fact, it is precariously floating on top of a sea which underpins it and holds it in being. No wonder the ego, through which we orientate ourselves in the world, is so fragile and prone to disintegration. Also, the mere fact that it exists in time means the self is divided from itself from one moment to the next, as David Hume suggested. Passive synthesis expresses itself through habit and Repetition, although, of course, that is only one half of the equation, since Difference is also involved. Difference is the transcendental ground of all empirical diversity and individuality, but it has to be organised through time, and this is where Repetition and habit enter the picture to make up the passive synthesis which underlies the active synthesis implicit in Kantian cognition. Yet, just as behind active synthesis lurks passive synthesis, behind passive synthesis lurks active synthesis. Of course, active synthesis doesn't just take place in (Kantian) cognition. It is active throughout nature and the self-organisation which lies at its heart. An example of this can be seen on YouTube. It involves a female cat suckling ducklings. What's strange about this is not the fact that a female cat had abandoned its predatory instincts to kill and eat ducklings, in order to mother them instead. After all, if it had lost its kittens and was still lactating, there is no reason on earth why it should not have sought a substitute for them. No, what is really strange is that ducks never suckle their young, so there could be no question of a genetic and instinctive form of behaviour kicking in as far as the ducklings were concerned. Quite the opposite in fact. Independently of any 'hard-wired' predispositions, the ducklings merrily took to sucking on the nipples of the cat and imbibing its milk. In short, a new and unprecedented habit was formed which the ducklings themselves inaugurated - active synthesis engendering a new passive synthesis as the ducklings learned to appreciate milk from their surrogate mother and repeat the practice into the future. So for Deleuze, a passive synthesis is not mechanistic, not something innate, any more than active synthesis. In fact, it must go through the phase of active synthesis before it can become established and then, of course, it must stop itself falling apart. That is active as well, though what you might call passively active. If Difference is "in-itself", repetition is always "for-itself", and not a mere product of mechanical inertia. Perhaps this is why Deleuze has so much time for the philosophy of Bergson, who postulated a creative dimension at the heart of evolution. In his book, Viroid Life, Keith Ansell Pearson writes that Darwinian Natural Selection merely prunes the phylogenetic tree; it does not cause it to grow. At the heart of evolution, in other words, a certain 'for-itself' initiative is being expressed which may or may not serve future generations. Perhaps what Deleuze means by passive synthesis is a dynamic and mobile structure supporting the activity implicit in active synthesis, a structure which expresses itself through Repetition and habits. However, that seems to be only one side of equation. The other side consists of active synthesis and activity, including the activity of adjusting this structure to new contingencies - as in the case of the ducklings and the lactating cat - and forming new habits. However, Deleuze's language is often so recondite that I am having to hazard my own interpretation of what he might mean based on no more than trains of thought which his words have set in motion in me. Likewise, with his critique of Kant, who seemed to believe that cognition was something given, something devoid of a structure in which it might be embedded. Kant also took for granted the unity of the subject - or self - in its subject-object field of perception, which Deleauze does not. According to Deleuze, each 'self' is repeated in time from each of its other selves as it has lived them in its past - or, more appropriately, its present-perfect - so that each present self recedes into the past and is displaced by another. This is what fractures the self in its sojourn through time. The memory of what it has been becomes an integral part of what it is without any longer being what it is. Thus the Self becomes fractured as it passes through time. Kant's 'self' took for granted a unity which it does not possess. In the same spirit, for Deleuze, Nietzsche's idea of the Eternal Return is not a return of the same or Identical, but a return of the Different. It is a kind of Return which lies at the heart of evolution itself - and not just of species, but of being itself. As in the case of the I which passes through time and becomes many Is, none of which are the same, what returns in the Eternal Return is never the same. This of course makes it a Dionysian rather than Apollonian idea, which one finds implicit in Kant's idea of a unified self. Repetition involves difference, not identity. The only identity which appears in repetition is the identity implicit in the concept. This dog, which wags its tail while I pet it, is different from the dog that five minutes ago was chasing a cat. It is only identical in the concept of "this dog". The concept confers on "this dog" an identity which it does not possess in being and is no more than a product of our representing "this dog" to ourselves. Like the I living in time, it is different from one moment to the next. It is a repeated dog, but not the same dog, except in so far as it comes under a concept - which, as Spinoza remarked, cannot bark. Between something existing in being and our representation of it in concepts lies a huge, unbridgeable chasm. Hegel's dialectic, for instance, is a false dialectic because it depends on negation and contradiction, which, in turn, depend on the identity of concepts opposing each other. And identity could be described in terms of something which always equals itself in the concept - e.g., dog = "dog" - which doesn't happen in being. Deleuze want's to replace Hegel's negative dialectic of opposition with an affirmative dialectic of difference, which is excessive rather than restrictive. Of course, in terms of art or poetry, this would involve an art or poetry that over-reached itself and overflowed all its boundaries in the process of completing itself - a Dionysian art. There are many aspects of Difference And Repetition which completely defeat me. For instance, Deleuze is obviously mathematically highly literate, which is the last thing I am. He is also far more literate regarding the special terminology of structuralist and post-structuralist discourse and indeed philosophy in general. Philosophy is always difficult, and so it should be if it is to be challenging. There, I think, it has something in common with poetry, though this would have nothing to do with a shared terminology or method of exposition. One thing they do have in common is that they go beyond taken for granted ideas and make the problematic their central concern. This is certainly the case with Deleuze. What matters for him is the question rather than the answer it might elicit; for he recognises that all original forms of discourse, whether poetic or philosophical, have their roots in ideas which are fundamentally problematic, along with questions which no one else asks.